1. Field of the Invention
The present invention relates to a semiconductor module, and more specifically, to a semiconductor module that can be attached to a heat sink.
2. Background Art
Regarding use of a semiconductor module, more specifically, a semiconductor module handling a great deal of electric power, the semiconductor device is generally attached to a heat sink for dissipation of heat generated while the semiconductor device is in operation. In order to transfer heat of the semiconductor module efficiently to the heat sink, heat conductive grease is applied between the semiconductor module and the heat sink (see Japanese Patent Application Laid-Open No. 2008-4745, for example).
Conventionally, an elastic member is arranged on the bottom surface of the semiconductor module by adhesive bonding. The semiconductor module is attached to the heat sink by adhesively bonding the elastic member and the heat sink with an adhesive.
The elastic member is arranged to surround heat conductive grease interposed between the semiconductor module and the heat sink, so that the elastic member also functions to prevent leakage of the heat conductive grease.
In the aforementioned conventional technique, the elastic member is adhesively bonded with an adhesive to the bottom surface of the semiconductor module and the heat sink. Thus, if adhesively bonded part is deteriorated by the influence of heat generation in the semiconductor module, for example, the heat conductive grease flows out from the deteriorated part. In this case, heat of the semiconductor module is not dissipated appropriately, leading to reduction of the performance of the semiconductor module.
If the adhesively bonded part is deteriorated further, the semiconductor module may fall off the heat sink.
The aforementioned problems are likely to occur, especially if the semiconductor module is attached at an angle not horizontal to the ground.